diff --git a/flang/lib/Lower/Bridge.cpp b/flang/lib/Lower/Bridge.cpp
--- a/flang/lib/Lower/Bridge.cpp
+++ b/flang/lib/Lower/Bridge.cpp
@@ -2731,12 +2731,15 @@
                 Fortran::lower::StatementContext stmtCtx;
                 if (Fortran::lower::isWholeAllocatable(assign.lhs))
                   TODO(loc, "HLFIR assignment to whole allocatable");
-                hlfir::EntityWithAttributes rhs =
-                    Fortran::lower::convertExprToHLFIR(loc, *this, assign.rhs,
-                                                       localSymbols, stmtCtx);
-                hlfir::EntityWithAttributes lhs =
-                    Fortran::lower::convertExprToHLFIR(loc, *this, assign.lhs,
-                                                       localSymbols, stmtCtx);
+                hlfir::Entity rhs = Fortran::lower::convertExprToHLFIR(
+                    loc, *this, assign.rhs, localSymbols, stmtCtx);
+                // Dereference pointers and allocatables RHS: the target is
+                // being assigned from.
+                rhs = hlfir::derefPointersAndAllocatables(loc, builder, rhs);
+                hlfir::Entity lhs = Fortran::lower::convertExprToHLFIR(
+                    loc, *this, assign.lhs, localSymbols, stmtCtx);
+                // Dereference pointers LHS: the target is being assigned to.
+                lhs = hlfir::derefPointersAndAllocatables(loc, builder, lhs);
                 builder.create<hlfir::AssignOp>(loc, rhs, lhs);
               },
               // [2] User defined assignment. If the context is a scalar
diff --git a/flang/lib/Optimizer/Builder/HLFIRTools.cpp b/flang/lib/Optimizer/Builder/HLFIRTools.cpp
--- a/flang/lib/Optimizer/Builder/HLFIRTools.cpp
+++ b/flang/lib/Optimizer/Builder/HLFIRTools.cpp
@@ -570,9 +570,9 @@
   if (entity.isMutableBox()) {
     hlfir::Entity boxLoad{builder.create<fir::LoadOp>(loc, entity)};
     if (entity.isScalar()) {
-      mlir::Type elementType = boxLoad.getFortranElementType();
-      if (fir::isa_trivial(elementType))
+      if (!entity.isPolymorphic() && !entity.hasLengthParameters())
         return hlfir::Entity{builder.create<fir::BoxAddrOp>(loc, boxLoad)};
+      mlir::Type elementType = boxLoad.getFortranElementType();
       if (auto charType = elementType.dyn_cast<fir::CharacterType>()) {
         mlir::Value base = builder.create<fir::BoxAddrOp>(loc, boxLoad);
         if (charType.hasConstantLen())
@@ -585,7 +585,10 @@
                 .getResult()};
       }
     }
-    // Keep the entity boxed for now.
+    // Otherwise, the entity is either an array, a polymorphic entity, or a
+    // derived type with length parameters. All these entities require a fir.box
+    // or fir.class to hold bounds, dynamic type or length parameter
+    // information. Keep them boxed.
     return boxLoad;
   }
   return entity;
diff --git a/flang/test/Lower/HLFIR/allocatable-and-pointer-subparts.f90 b/flang/test/Lower/HLFIR/allocatable-and-pointer-subparts.f90
--- a/flang/test/Lower/HLFIR/allocatable-and-pointer-subparts.f90
+++ b/flang/test/Lower/HLFIR/allocatable-and-pointer-subparts.f90
@@ -26,7 +26,8 @@
 ! CHECK:  %[[VAL_1:.*]]:2 = hlfir.declare %{{.*}} {{.*}}Ex
 ! CHECK:  %[[VAL_2:.*]] = hlfir.designate %[[VAL_1]]#0{"p"}   {fortran_attrs = #fir.var_attrs<pointer>} : (!fir.ref<!fir.type<_QMmTt2{p:!fir.box<!fir.ptr<!fir.type<_QMmTt1{x:f32}>>>}>>) -> !fir.ref<!fir.box<!fir.ptr<!fir.type<_QMmTt1{x:f32}>>>>
 ! CHECK:  %[[VAL_3:.*]] = fir.load %[[VAL_2]] : !fir.ref<!fir.box<!fir.ptr<!fir.type<_QMmTt1{x:f32}>>>>
-! CHECK:  %[[VAL_4:.*]] = hlfir.designate %[[VAL_3]]{"x"}   : (!fir.box<!fir.ptr<!fir.type<_QMmTt1{x:f32}>>>) -> !fir.ref<f32>
+! CHECK:  %[[VAL_4:.*]] = fir.box_addr %[[VAL_3:.*]] : (!fir.box<!fir.ptr<!fir.type<_QMmTt1{x:f32}>>>) -> !fir.ptr<!fir.type<_QMmTt1{x:f32}>>
+! CHECK:  hlfir.designate %[[VAL_4]]{"x"}   : (!fir.ptr<!fir.type<_QMmTt1{x:f32}>>) -> !fir.ref<f32>
 
 subroutine test_symbol_followed_by_ref(x)
   character(:), allocatable :: x(:)
diff --git a/flang/test/Lower/HLFIR/assignment-intrinsics.f90 b/flang/test/Lower/HLFIR/assignment-intrinsics.f90
--- a/flang/test/Lower/HLFIR/assignment-intrinsics.f90
+++ b/flang/test/Lower/HLFIR/assignment-intrinsics.f90
@@ -135,6 +135,17 @@
 ! CHECK:  %[[VAL_11:.*]]:2 = hlfir.declare {{.*}}  {uniq_name = "_QFarray_characterEy"} : (!fir.ref<!fir.array<10x!fir.char<1,?>>>, !fir.shape<1>, index) -> (!fir.box<!fir.array<10x!fir.char<1,?>>>, !fir.ref<!fir.array<10x!fir.char<1,?>>>)
 ! CHECK:  hlfir.assign %[[VAL_11]]#0 to %[[VAL_6]]#0 : !fir.box<!fir.array<10x!fir.char<1,?>>>, !fir.box<!fir.array<10x!fir.char<1,?>>>
 
+subroutine array_pointer(x, y)
+  real, pointer :: x(:), y(:)
+  x = y
+end subroutine
+! CHECK-LABEL: func.func @_QParray_pointer(
+! CHECK:  %[[VAL_1:.*]]:2 = hlfir.declare %{{.*}}Ex
+! CHECK:  %[[VAL_2:.*]]:2 = hlfir.declare %{{.*}}Ey
+! CHECK:  %[[VAL_3:.*]] = fir.load %[[VAL_2]]#0 : !fir.ref<!fir.box<!fir.ptr<!fir.array<?xf32>>>>
+! CHECK:  %[[VAL_4:.*]] = fir.load %[[VAL_1]]#0 : !fir.ref<!fir.box<!fir.ptr<!fir.array<?xf32>>>>
+! CHECK:  hlfir.assign %[[VAL_3]] to %[[VAL_4]] : !fir.box<!fir.ptr<!fir.array<?xf32>>>, !fir.box<!fir.ptr<!fir.array<?xf32>>>
+
 ! -----------------------------------------------------------------------------
 !     Test assignments with array LHS and scalar RHS
 ! -----------------------------------------------------------------------------